Process of refining crude cotton-seed oil.



UNITED srnrns PATENT OFFICE.

anssn c. cnrsnomu, or names, 'rnxas.

PROCESS OF REFINING CRUDE COTTON-SEED OIL.

No Drawing.

Specification of Letters Patent.

To all whom it may concern Be it known that I, Jnssn G. CHISHOLM, acitizen of the United States, residing at Dallas, in the county ofDallas and State of Texas, have invented certain new and usefulImprovements in Processes of Refining Crude Cotton-Seed Oil, of whichthe following is a specification.

This invention relates to processes of refining oil and has particularreference to a process of refining crude cotton seed o l designed toincrease the yield of refined 011 of the required color, odor andflavor.

In Letters Patent No. 1,007,6e2, for a process of refining crude cottonseed oil,

anted to me-under date of October 31, 1911, I have described and claimeda process of refining cotton seed oil which consists 1n subjecting theoil to the action of an alkaline silicate until the acidity of the oilis approximately overcome, then subjecting it to the action of analkaline hydrate and finally separating the oil from the soap stockformed. Now I have discovered that this process may in some cases beadvantageously changed by employing a mixture of an alkaline silicateand another alkaline compound preferably an alkaline carbonate insteadof the alkaline silicate alone, for the initial neutralization of theoil.

In the practice of my process crude cotton seed oil istreated with anaqueous solution of a water soluble alkalinesilicate, preferably sodiumsilicate (Na Si O mixed with an aqueous solution of another alkalinecompound preferably an alkaline carbonate as sodium carbonate (Na CQuntil the acidity of the oil is approximately overcome. The proportionof the alkaline silicate to the alkaline carbonate in the mixture mayvary widely. I have found however that satisfactory results may beobtained by employing a mixture of equal partseby weight of an aqueousalkaline silicate solution of approximately 50 Baum and an aqueousalkaline carbonate solution of approximately 30 Baum. The mixture isadded to the oil until the latter is approximately neutralized. Thisordinarily requires from one to three parts by weight of the mixture to100 parts by weight of crude oil. After the alkaline solution is addedto the oil the mixture is stirred or otherwise agitated at a temperatureof approm'mately 75 to 90: F, the agitation being continued and thetemperature maintained until the oil I grains from the separation ofsoap stock,

and the yellow color of the foam on the oil changes to a darker shade.This effect takes place when the fatty acids contained in the oil areentirely neutralized by the action of Patented Mar.- 18, 1913.

Application filed October as, 1911. Serial No. 656,811.

the alkaline solution which has been added -thereto. There is thengradually added to the mixture from two to eight per cent. by weight ofa solution of alkaline hydroxid, preferably sodium hydroxid of from 12to 22 Baum. This alkaline hydroxid solutipn is added until a filteredsample of the mixture shows an oil of the required color. Havingobtained oil of the required color the addition of the alkaline hydroxidis conf tinued and tests are made from time to time upon removedsamples, by heating such samples to preferably from approximately 120 to140 F., the alkaline hydroxid solution being added until such samplesare found to reach the critical point, that is to say, the point atwhich the soap stock precipitate in the sample will settle rapidly andcompletely from the oil and be practically free from contained oil. Whenthis point is reached no further addition of the alkaline hydroxid ismade. The oil is stirred -or otherwise agitated while being treated withthe alkaline hydroxid. The mass of treated oil is then heated topreferably from 100 to 120 F., the mixture being agitated during suchheating. The heating and agi-- tating are continued until the soap stockparticles agglomerate and a test of a removed sample of the oil showsthat the soap stock therein will settle rapidly andcompletely from therefined oil. The oil is then allowed tostand preferably from two totwenty-four hours until the soap stock has completely settled; Thesupernatant oil is then drawn OE and heated to preferably about 150 F.,to free the same from water. If desired, air may be pumped through therefined oil to accelerate the drying operation. The refined oil is thenfiltered.

While in the practical operation of my process I prefer to heat the oilas indicated, some measureof success in the practice of the process maybe obtained without subjecting the oil to artificial heat. In summer aconsiderable measure of success may be obtained throughout the SouthernStates without any application of artificial heat. At other seasons ofthe year and inother sections of this country, some measure .of

ment with the reagents set forth, Without any application of heatWhatever, but the practice of the process can be carried out mostettectively under the conditions of tem perature hereinbetore set forth.

/Vhile .l have set forth in detail the strength of the solutions and theproportions of the various reagents which I prefer to employ, it is tobe understood that my proc ess is not restricted theretoQbut that thestrength of such solutions and the proportions may be Widely varied,ithout depart ing from the spirit of my invention or the scope of theappended claims. This Wide Variation in the strength of solution and theproportions of the reagents is necessitated by reason of the Widelyvarying characters of the crude cotton seed oils received for refining.

Having thus described my invention, 1 claim v 1. The process of refiningcrude cotton seed oil which consists in subjecting it to the action ofan alkaline silicate and another alkaline compound until the acidity ofthe oil is approximately overcome, then subjecting it to the action ofan alkaline hydroxid and separating the oil from the soap vstock formed.

2. The process of refining crude cotton seed oil which consists in subecting it to the action of a mixture of an alkaline silicate and analkaline carbonate, the mixture be ing added until the acidity of theoil is approximately overcome, then subjecting it to the action of analkaline hydroxid and separating the oil from the soap stock formed.

3. The process of refining crude cotton 3 inoaaaoa seed oil whichconsists in subjecting it to the action of heat and. a mixture of analkaline silicate and an alkaline carbonate,'the mixture being addeduntil the acidity of the oil is approximately overcome, then subjectingit to the action of an alkaline hydroxid and separating the oil from thesoap stock formed.

t The process of refining crude cotton seed oil Which consists inagitating the oil at a temperature of about 80 F, an aqueous solution ofan alkaline silicate and an alkaline carbonate being added thereto untilthe acidity of the oil is approximately overcome, maintaining thetemperature of the mixture at from approximately 75 to 90 F, until theseparation of the soap stock is apparent in the oil, adding an aqueoussolution of an alkaline hydroxid, maintaining the temperature of the oiluntil a test-sample of the mixture shows the required color, addingadditional alkaline hydroxid until in a test sample of the mixtureremoved and heated to approximately from 120 to 140 F, the soap stockprecipitate separates readily and completely from the oil, then'heatingthe mass of treated oil to preferably from 100 to 120,F., such heatingbeing continued until the soap stock settles rapidly and com pletelyfrom the oil allowing the soap stock to settle and separating the oilfrom the soap stock.

In testimony whereof I do atfix my signature in presence of tWoWitnesses.

JESSE C. CHTSHQLld- Witnesses M. M. CRANE, N. M. Coon.

